1. Field
The disclosed concept relates generally to electrical switching apparatus and, more particularly, to electrical switching apparatus, such as switches. The disclosed concept also relates to stored energy assemblies for switches. The disclosed concept further relates to energy storage and release control mechanisms for stored energy assemblies of electrical switching apparatus.
2. Background Information
Electrical switching apparatus, such as quick make-quick break (QMQB) switches, provide a switching capability and safe short circuit closing capability for electrical systems from electrical fault conditions such as, for example, current overloads, short circuits, abnormal voltage and other fault conditions, and switching electrical loads on and off. Typically, QMQB switches include an operating mechanism which closes or opens electrical contact assemblies to initiate or interrupt the flow of load current through the conductors of an electrical system.
Some medium voltage switches, for example, employ a spring-operated stored energy assembly. Specifically, the operating mechanism of such switches typically includes an operating assembly having one stored energy mechanism (e.g., spring) which facilitates the closing and opening (e.g., separation) of the electrical contact assemblies, and a charging mechanism for charging the spring. The contact assemblies are closed or opened by releasing the stored energy when the charging mechanism has finished charging the operating spring and “toggles” to release the spring's energy of the operating assembly spring. The operating assembly spring is charged either manually, using a manual charging mechanism such as, for example, a charging handle, or automatically using, for example, a motor-driven charging mechanism or other suitable electromechanical charging mechanism.
Inappropriate release of stored energy from the spring can result in damage to the switch operating mechanism. It can also compromise the safety of personnel operating the switch. Prior proposals have employed electrical means for preventing the undesired release of stored energy. However, such designs are susceptible to defeat, for example, by operating personnel error.
There is, therefore, room for improvement in electrical switching apparatus, such as switches, and in stored energy assemblies and energy storage ands therefor.